I used Umbrel for 2.5+ years. It worked great. It's a solid product. I switched to a home grown solution because I wanted a little more freedom to run different apps.

Me too, even compiled the BTC core and lnd myself - don't trust, verify 🙂 (if you can)

Is it too i/o intensive? can i use a NAS via NFS? Using NFS seems stabler than using external USB disks in raspberry pi.

Just the initial load of the Blockchain, it's about 600 GB. Later it's just ln gossip and about a block every 10 minutes 🌞

It's stable with external power supply at the SSD